JP2005128470A - Electrochemical table display medium, display element and display device using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reflection type electrochemical display medium whose visibility and texture are very similar to paper, a display element using the same, and a display device using the display element. SOLUTION: An organic solution (A) obtained by dissolving a compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound and a phosgene compound in an organic solvent, an alkali silicate and / or two or more metal elements. A basic element containing at least one metal compound (1) selected from the group consisting of metal oxides, metal hydroxides and metal carbonates, wherein one of the metal elements is an alkali metal, and a diamine Electrochemical display medium and display element, which are a composite of an organic polymer and an inorganic compound obtained by mixing and stirring an aqueous solution (B) and causing a polycondensation reaction, wherein the composite holds an electrolytic solution And a display device.
[Selection figure] None

Description

  The present invention provides a reflective electrochemical display medium that has very close visibility and texture similar to paper, a display element using the same, and a display device.

  Various technologies have been researched and developed so far for display elements. Among them, various methods have been studied for display elements using reflected light, which are said to have high visibility and are easy on the eyes. The display element with reflected light has the greatest advantage that it can withstand long-term use because the display surface follows the ambient brightness and directional vertical light does not enter the eye. However, in order to make full use of this advantage, it is important how to produce natural and soft whiteness close to paper due to light scattering. For this reason, one of the biggest development goals is how to bring the visibility and texture of the display surface closer to paper.

A display device using liquid crystal, which is one of the technologies of the reflected light type display device, is the most widely used technology at present, but since this method requires a polarizer, the reflected light intensity is greatly attenuated, The whiteness of the display surface does not reach that of paper. In addition, there is a problem that viewing angle dependency occurs. As another display method, a so-called particle rotation type display is known in which display is performed by rotating particles (two-color particles) having two-color regions having different hues and charging characteristics (for example, Patent Documents). 1). Due to the structure of the two-color rotating particles, when the viewing surface side is light (for example, white), the opposite side is dark (for example, black). Even if the two-color particles are arranged densely, a gap is always generated. For this reason, when light coming from the viewing surface in bright color display enters a gap generated by the arranged two-color particles, most of the light is absorbed by the dark color surface on the opposite side. Is low and it is difficult to obtain whiteness close to that of paper.

In the case of a display element using a particle migration method, generally, white display is performed by moving pigment fine particles such as titanium oxide to the viewing surface side of the display device (for example, see Patent Document 2). However, in this method, since the mechanism for producing whiteness is fundamentally different from that of paper, natural whiteness such as that of paper cannot be produced due to a grainy feeling or the like.

On the other hand, as another display element that uses reflected light, an electrochemical display element that uses a reversible change in hue that occurs in a solid or liquid when a voltage is applied is known. With this device, it is possible to perform excellent display with clear hue and no viewing angle dependency during colored display. An electrochromic having a polymer material layer discolored by electrochemical oxidation and reduction existing on a transparent electrode, and a polymer solid electrolyte layer containing a colorant such as titanium oxide in contact with the polymer material layer A type display element is known (see, for example, Patent Document 3). The patent document also describes an electrodeposition type display element in which a polymer solid electrolyte layer containing a colorant such as titanium oxide and a metal ion as a color former is sandwiched between electrodes. In addition, a white semiconductor or insulator powder such as titanium oxide or magnesium oxide is dispersed in an electrolytic solution in which a silver salt (color former) and a supporting electrolyte are dissolved in a solvent, and this liquid is sandwiched between transparent electrodes. An electrodeposition type display device is described (for example, Patent Document 4).

In any of the methods disclosed in Patent Documents 3 and 4, since so-called white pigment is used to give whiteness to the display element, the visibility and texture of the display element are greatly different from those of paper. In addition, in the electrochemical display element, it is necessary to smoothly move ions between the counter electrodes when performing display, but in the method using the polymer electrolyte disclosed in Patent Document 3, when an electrolytic solution is used. In contrast, since the ionic conductivity is low, the display response speed is slow, and the drive voltage may be increased. In addition, since the temperature dependence of ion conductivity is greater than when a liquid electrolyte is used, stable driving in a wide temperature range, particularly at low temperatures, is difficult. On the other hand, if the electrolytic solution is used in the display element in a liquid state as in Patent Document 4, leakage or the like is liable to occur when the display element is damaged, and the white powder is unevenly distributed. There is a risk that uniform whiteness cannot be produced.
U.S. Pat. No. 4,126,854 JP-A-1-86116 Japanese Patent Laid-Open No. 14-258327 U.S. Pat.No. 4,240,716

It is an object of the present invention to provide a reflection type electrochemical display medium having visibility and texture very close to paper, a display element using the same, and a display device.

  The present inventors include an organic solution (A) obtained by dissolving one kind of compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound, and a phosgene compound in an organic solvent, an alkali silicate and / or two or more kinds. A basic composition comprising at least one metal compound selected from the group consisting of metal oxides, metal hydroxides and metal carbonates, wherein the metal element has one of the metal elements and an alkali metal, and a diamine. A wet cake sheet holding an electrolytic solution in which a supporting electrolyte is dissolved in a composite of an organic polymer and an inorganic compound obtained by mixing and stirring the aqueous solution (B) and performing a polycondensation reaction, has extremely high visibility. White substrate close to paper and having high reflectivity, ion conductor exhibiting a function of holding a large amount of electrolyte in a gel state, and interelectrode separator having high electronic insulation And combines the three functions of terpolymers, found that can be used as an electrochemical display medium, thereby completing the present invention.

That is, the present invention
An organic solution (A) obtained by dissolving a compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound, and a phosgene compound in an organic solvent, an alkali silicate, and / or a metal having two or more metal elements A basic aqueous solution (B) containing at least one metal compound (1) selected from the group consisting of metal oxides, metal hydroxides and metal carbonates, wherein one of the elements is an alkali metal, and diamine And a mixture of an organic polymer and an inorganic compound obtained by mixing and stirring, and an electrochemical display medium in which the composite holds an electrolytic solution.

  In addition, an electrochemical display element having the electrochemical display medium of the present invention is provided between two substrates having electrodes facing each other with the electrodes facing inside.

  Also provided is an electrochemical display device comprising the electrochemical display element.

Further, an organic solution (A) in which a compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound, and a phosgene compound is dissolved in an organic solvent,
At least one metal compound selected from the group consisting of metal oxides, metal hydroxides, and metal carbonates, having an alkali silicate and / or two or more metal elements and one of the metal elements is an alkali metal ( 1) and a basic aqueous solution (B) containing a diamine are mixed and stirred, and a composite synthesis step for obtaining a composite of an organic polymer and an inorganic compound obtained by polycondensation reaction;
Provided is a method for producing an electrochemical type display medium, which comprises an impregnation step of impregnating an electrolytic solution with the solid content of the composite being 35% by mass or less and holding the electrolytic solution in the composite.

  According to the present invention, it is possible to provide a reflection type electrochemical display medium that is very similar in visibility and texture to paper, a display element using the same, and a display device.

The electrochemical display medium of the present invention, the display element using the same, and the display device are very close to paper in terms of visibility and texture. In addition, the response speed is higher than that of an electrochemical display medium using a polymer electrolyte, the power consumption is low, and the usable temperature range is wide. In addition, the display medium in the present invention does not leak unlike a display medium that uses the electrolytic solution in a liquid state.

In addition, the electrochemical display medium of the present invention is an organic-inorganic composite having a high ability to retain an electrolytic solution, unlike a structure in which an organic polymer and an inorganic compound are simply mixed. As a preferred embodiment, the organic-inorganic composite can hold an electrolyte solution having a mass of 4 to 25 times its own weight. In order to obtain a display medium with higher contrast, it is preferable to hold 5 to 20 times the mass of the electrolytic solution.

The display medium of the present invention comprises a dicarboxylic acid halide, a dichloroformate compound, and a phosgene compound as a member having three functions of a white body of a display element, an ionic conductor holding an electrolytic solution, and an interelectrode separator. An organic solution (A) obtained by dissolving one kind of compound selected from the group in an organic solvent;
At least one metal compound selected from the group consisting of metal oxides, metal hydroxides, and metal carbonates, having an alkali silicate and / or two or more metal elements and one of the metal elements is an alkali metal ( 1) and a basic aqueous solution (B) containing a diamine are mixed and stirred, and a complex of an organic polymer and an inorganic compound obtained by polycondensation reaction is used. The composite obtained by this method has a high content of 15 to 80% by mass of inorganic fine particles of submicrometer to nanometer order in polyamide, polyurethane and polyurea as organic polymers with respect to the total mass of the composite. And can be finely dispersed. In order to retain a large amount of electrolyte and to give high light scattering efficiency by widening the interface region between the organic polymer and inorganic particles and to obtain high whiteness, the inorganic content in the composite is 20 to 20%. It is preferable that it is 70 mass%.

The organic-inorganic composite used in the present invention reacts rapidly with the monomer in the organic solution (A) and the diamine in the aqueous solution (B) by stirring for about 10 seconds to several minutes at room temperature and normal pressure. The organic polymer component can be obtained with good yield. At that time, the alkali metal in the alkali silicate and / or the metal compound (1) acts as a removing agent for the hydrogen halide generated during the polymerization, thereby promoting the polymerization reaction of the organic polymer. Simultaneously with this reaction, the alkali metal silicate and / or metal compound (1) has its alkali metal compound component removed, and when alkali silicate is used, it is converted to silica, and when metal compound (1) is used, other than alkali metal. By converting into a metal compound having a metal element, it becomes insoluble in water and precipitates as a solid. At that time, since the polymerization reaction of the organic polymer and the conversion of the silica and / or metal compound into a solid occur in parallel without causing only one of them, the silica and / or metal compound fine particles are finely dispersed in the organic polymer. A dispersed organic-inorganic composite is obtained.

  Examples of the dicarboxylic acid halide used in the organic solution (A) in the present invention include aliphatic dicarboxylic acid acid halides such as succinic acid, adipic acid, azelaic acid, and sebacic acid, and aromatics such as isophthalic acid and terephthalic acid. Examples include acid halides of dicarboxylic acids, or acid halides of aromatic dicarboxylic acids obtained by substituting hydrogen of these aromatic rings with halogen atoms, nitro groups, alkyl groups, and the like. These may be used alone or in combination of two or more. Can be used in combination.

  Examples of the dichloroformate compound used in the organic solution (A) in the present invention include 1.2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8- Aliphatic diols such as octanediol, resorcin (1,3-dihydroxybenzene), hydroquinone (1,4-dihydroxybenzene), 1,6-dihydroxy having two or more hydroxyl groups on one or more aromatic rings Mention may be made of all the hydroxyl groups of dihydric phenols such as naphthalene, 2,2′-biphenol, bisphenol S, bisphenol A, tetramethylbiphenol, etc., which have been chloroformated by phosgenation treatment. These can be used alone or in combination of two or more.

  Examples of the phosgene compound used in the organic solution (A) in the present invention include phosgene and triphosgene. These may be used alone or in combination of both species.

  In the present invention, the matrix organic polymer of the organic-inorganic composite can be changed by selecting the monomer used in the organic solution (A). Polyamide can be obtained by reaction with an aqueous solution (B) when a dicarboxylic acid halide is used as a monomer, a polyurethane when a dichloroformate compound is used, or a polyurea when a phosgene compound is used. it can.

  As an organic solvent used in the organic solution (A) in the present invention, any solvent that does not react with the various monomers and diamines in the organic solution (A) and dissolves the various monomers in the organic solution (A) can be used. It can be used without particular limitation. Among these, those incompatible with water include aromatic hydrocarbons such as toluene and xylene, aliphatic hydrocarbons such as n-hexane, halogenated hydrocarbons such as chloroform and methylene chloride, and alicyclic rings such as cyclohexane. Representative examples of the hydrocarbons compatible with water include ethers such as tetrahydrofuran, ketones such as acetone and methyl ethyl ketone, and the like.

  When an organic solvent incompatible with water is used as the organic solvent used in the organic solution (A), the resulting polycondensation reaction is interfacial polycondensation that occurs in the vicinity of the interface between the aqueous solution (B) and the organic solution (A). . In this case, since the molecular weight of the obtained organic polymer can be easily increased, a fiber-shaped composite is easily obtained. Moreover, a high-strength long fiber can also be obtained by spinning while pulling up the composite film formed at the interface between the aqueous solution (B) and the organic solution (A). Conversely, when an organic solvent that is compatible with water is used, polymerization occurs in a state where the organic solvent and water are emulsified, so that a powder-shaped composite can be easily obtained.

  Regardless of which organic solvent is used, the resulting organic / inorganic composite has a larger external surface area than powder or pulp and bulk, so that it is easy to use the electrolyte without the need for processing such as grinding. Can be retained.

The diamine used in the aqueous solution (B) in the present invention can be used without particular limitation as long as it reacts with each monomer in the organic solution (A) to produce an organic polymer. Specifically, aliphatic diamines such as 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, 1,6-diaminohexane, 1,8-diaminooctane, and m-xylylenediamine , Aromatic diamines such as p-xylylenediamine, m-phenylenediamine, p-phenylenediamine, 1,5-diaminonaphthalene, 1,8-diaminonaphthalene, 2,3-diaminonaphthalene, or hydrogen of these aromatic rings. Examples include aromatic diamines substituted with halogen atoms, nitro groups, alkyl groups, and the like. You may use these individually or in combination of 2 or more types.

The monomer concentration in the organic solution (A) and the aqueous solution (B) in the present invention is not particularly limited as long as the polymerization reaction proceeds sufficiently, but from the viewpoint of bringing the monomers into good contact with each other, 0.01 to 3 A concentration range of mol / L, particularly 0.05 to 1 mol / L is preferred.

In the present invention, a composite composed of an organic polymer and silica can be obtained and used as a display medium by carrying out a polymerization reaction in the presence of an alkali silicate in the aqueous solution (B). The alkali silicate used in the aqueous solution (B) in the present invention is represented by a composition formula of A ₂ O · nSiO ₂ such as water glass No. 1, No. 2, No. 3, etc. described in JIS K 1408, and A is an alkali metal. , N has an average value of 1.8 to 4. Moreover, the liquid which melt | dissolved the powder of alkali metasilicate (for example, sodium metasilicate 1 type, 2 types) whose average value of n is 0.8-1.1 in water can be used similarly to water glass. . The alkali metal compound contained in the alkali silicate acts as an acid remover when it is generated during the polymerization, thereby promoting the polymerization reaction and at the same time acting as an inorganic raw material that is converted into solid silica.

Moreover, in this invention, the metal compound which has metal elements other than the alkali metal in an organic polymer and a metal compound (1) by making it superpose | polymerize in the state which made the metal compound (1) coexist in aqueous solution (B). Can be used as a display medium. As a metal compound (1) to be used, the compound which can be represented as general formula AxMyBz can be mentioned. A group in which A is an alkali metal element, M is at least one metal element selected from the group consisting of metal elements other than alkali metals, and B is at least one type selected from the group consisting of O, CO ₃ and OH The thing which is is mentioned. x, y, and z are numbers that allow A, M, and B to be combined. The compound represented by the general formula AxMyBz is preferably a compound that dissolves in water and exhibits basicity. Similarly to the alkali metal compound in the alkali silicate, the alkali metal contained in the metal compound (1) also acts as an acid remover when generated during the polymerization, thereby promoting the polymerization reaction.

Among the metal compounds (1) used in the present invention, the compounds in which B in the above general formula is O include sodium zincate, sodium aluminate, sodium chromite, sodium molybdate, sodium stannate, tellurium. Sodium complex oxides such as sodium oxide, sodium titanate, sodium vanadate, sodium tungstate, potassium zincate, potassium aluminate, potassium chromite, potassium molybdate, potassium stannate, potassium manganate, potassium tantalate Of potassium complex oxides such as potassium tellurite, potassium ferrate, potassium vanadate, potassium tungstate, potassium goldate and potassium silverate, lithium complex oxides such as lithium aluminate, lithium molybdate and lithium stannate Other rubidium complex oxidation , It can be used cesium complex oxide.

Examples of the alkali metal compound (1) in which B in the above general formula includes one or both of CO ₃ and OH include zinc carbonate potassium, nickel carbonate potassium, potassium zirconium carbonate, cobalt potassium carbonate, and potassium tin carbonate. And their hydrates can be exemplified

Since these metal compounds (1) are dissolved in water and used, they may be hydrates. Moreover, these can be used individually or in combination of 2 or more types. Moreover, you may use simultaneously with the above-mentioned alkali silicate.

The concentration of the alkali silicate and / or metal compound (1) in the aqueous solution (B) is determined to some extent by the monomer concentration in the organic solution (A) and the aqueous solution (B). 1 to 200 g / L is desirable for the purpose of preventing the side reaction between the monomer in the organic solution (A) and water that may be generated by excessive heat generation during polymerization.

  The alkali silicate and / or metal compound (1) coexisting in the interfacial polycondensation reaction field also has an action of accelerating the polycondensation reaction by neutralizing the hydrogen halide generated during the polycondensation reaction, so that the blending amount thereof is small In the case where the generated hydrogen halide inhibits the progress of the polycondensation reaction, the acid acceptor may be added even if an acid acceptor such as sodium hydroxide, potassium hydroxide, sodium carbonate or potassium carbonate is added to the aqueous solution (B). The solution may be added later to the synthesis system.

  In the present invention, the organic-inorganic composite is provided with the three functions of the white body of the display element, the ionic conductor holding the electrolytic solution, and the interelectrode separator. Therefore, as the best mode of the composite, it can be mentioned that any of whiteness, electrolyte retention property, and electronic insulation property is high. In order to impart these characteristics, it is particularly preferable to select the following materials for each component of the organic solution (A) and the aqueous solution (B).

The characteristics of the white body in the present invention are manifested by the colors of the organic and inorganic components of the organic-inorganic composite, the organic-inorganic composite state, and the shape of the composite.

As the organic component of the organic-inorganic composite for imparting high whiteness, a raw material that gives a polymer having high whiteness is preferably used, and a material that gives colorless or white fine particles is preferably used as the inorganic component.

If the inorganic particles that make up the organic-inorganic composite are on the order of submicrometers larger than the visible light wavelength and are colorless or white, and the refractive index difference between the organic polymer and the organic polymer is large, between the interface between the organic polymer and the inorganic particle Light scattering occurs efficiently, giving the composite a very good whiteness. At this time, the size of the inorganic particles is preferably a particle having a size of about 800 nanometers to about 1 micrometer which is slightly larger than the visible light wavelength. When there are a large amount of particles in this region, the interface area between the organic polymer and the inorganic particles becomes relatively wide, and light scattering occurs favorably, and high whiteness can be imparted to the composite. Examples of such inorganic components include zirconium oxide, zinc oxide, and tellurium oxide (IV). Examples of the metal compound (1) as an inorganic raw material that can be combined with an organic-inorganic composite include alkali metal composite oxides such as sodium zincate, potassium zincate, sodium tellurite and potassium tellurite, and potassium zinc carbonate. And alkali metal composite carbonates such as potassium potassium carbonate.

On the other hand, in the case where the inorganic material is silica or aluminum oxide, the inorganic particle diameter is very small, about 10 nanometers, and it is a transmission electron that the inorganic particles are partly connected to form a network structure. It becomes clear by observation with a microscope (TEM). At this time, if the size of the entire network composed of inorganic particles is larger than the wavelength of visible light, visible light scattering occurs with high efficiency at the very wide interface of the organic-inorganic composite. Can be given to the body. Examples of such inorganic raw materials that can impart inorganic components and structures include alkali silicates such as sodium silicate and potassium silicate, and alkali aluminates such as sodium aluminate and potassium aluminate.

In addition, when the main chain of the organic polymer constituting the organic-inorganic composite is aliphatic, it is preferably used because it has no conjugated structure and thus does not absorb visible light and has high whiteness. Monomers used in the organic solution (A) for producing such a polymer include acid halides of aliphatic dicarboxylic acids such as succinic acid, adipic acid, azelaic acid and sebacic acid, 1.2-ethanediol, 1,3 An aliphatic chloroformate compound in which hydroxyl groups of aliphatic diols such as propanediol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol and the like are all chloroformated by phosgenation treatment, Examples include phosgene compounds of phosgene, diphosgene and triphosgene. Examples of the diamine used in the aqueous solution (B) include aliphatic diamines such as 1,3-diaminopropane, 1,4-diaminobutane, and 1,6-diaminohexane.

Among these, in particular, aliphatic dicarboxylic acid halides as organic solvents (A) and solvents such as toluene, n-hexane, cyclohexane, methylene chloride, carbon tetrachloride, which are incompatible with water, are used as aqueous solutions (B) as aliphatics. When diamine is used, polycondensation becomes interfacial polycondensation between (A) and (B), and the molecular weight can be easily increased. Therefore, by applying a high shear force during synthesis, the fiber diameter is 20 μm or less. It can also be processed into a shape whose main component is a pulp (bent microfiber) having an aspect ratio of 10 or more. The composite having such an appearance can be made into paper, and by making this, a sheet-like wet cake having an appearance almost equal to that of paper can be obtained without using a binder or the like. Since the wet cake sheet obtained by making a pulp-shaped article has random and minute irregularities on the surface, incident light is scattered in each direction, and more natural and soft whiteness can be obtained.

The characteristics of the electrolyte solution holding material in the present invention are expressed by the chemical characteristics and shape factors of the organic and inorganic components of the organic-inorganic composite.

The role of the inorganic component in the organic-inorganic composite is considered as follows. The inorganic particles of the composite are composed of a substance having an extremely high affinity for a polar solvent, which is composed of silica and / or metal oxide, carbonate, or hydroxide. In addition, the content of the inorganic particles is as high as 15 to 80% by mass, and the size of the inorganic particles is extremely small, on the order of submicrometers to nanometers.

The fact that the inorganic particles are on the order of submicrometer to nanometer means that an infinite number of inorganic fine particles having a very large surface area per unit weight are present in the composite. By imparting a strong affinity for a polar solvent to the wide surface of these inorganic fine particles, the composite exhibits high electrolyte solution retention characteristics. In addition, since the composite can have an extremely high inorganic content of 80% at the maximum, the above-mentioned characteristics of the inorganic fine particles can be further enhanced.

In particular, when the inorganic material is silica or aluminum oxide, the inorganic particle diameter is as very small as about 10 nanometers as described above, and a network structure in which the inorganic particles are partially connected is formed. With this structure, the composite has a high specific surface area (that is, porosity) of 50 to 150 m ² / g, and can have higher electrolyte retention. As described above, inorganic raw materials that can impart such a structure are alkali silicate and alkali aluminate.

On the other hand, it is considered that the role of the organic component with respect to the electrolyte retention property is as follows. Polyamide, polyurethane, and polyurea, which are organic components of the composite, are derived from the high polarity of amide, urethane, and urea bonds that they frequently have, and have extremely high polar solvent affinity compared to polyolefin and the like. Therefore, since the component also contributes to the retention property of the polar solvent, any of the aforementioned organic polymers can be suitably used. Moreover, especially when it has a pulp shape, it is possible to hold | maintain electrolyte solution firmly between the fibers of an organic inorganic composite, and it is possible to further raise a solvent retention amount and retention strength. As described above, the raw material capable of giving this shape is an aliphatic diamine as an aqueous solution (B) for a system in which an acid halide of an aliphatic dicarboxylic acid is dissolved in a water-incompatible solvent as the organic solvent (A). In the case of reaction.

The characteristics of the separator having an electronic insulating property in the present invention are characteristics that can be expressed without problems unless a material having electronic conductivity is used for each of the organic and inorganic components of the organic-inorganic composite.

As an inorganic raw material, for example, when using an alkali component such as sodium stannate and potassium stannate that can provide tin oxide having electronic conductivity and potassium tin carbonate, the inorganic component is made a high proportion of 60% by mass. Although attention is required for use, all other inorganic raw materials can be used without any problem. In addition, even when the organic component is polyamide, polyurethane, or polyurea, it does not have electronic conductivity, so that it can be used without any problem.

As described above, an organic-inorganic composite having three functions of a white body formed from a fiber-shaped material close to the paper of the display element, an ionic conductor holding an electrolytic solution, and an interelectrode separator is synthesized as a particularly preferable composition and shape. Examples of the raw material include an organic solvent (A) in which an acid halide of an aliphatic dicarboxylic acid is dissolved in a solvent incompatible with water, and an aliphatic diamine and an alkali silicate and / or alumina as an aqueous solution (B). A system in which an acid alkali is dissolved can be used. Further, as inorganic raw materials in the aqueous solution (B), alkali metal composite oxides such as sodium zincate, potassium zincate, sodium tellurite and potassium tellurite, and alkali metal composite carbonates such as zinc carbonate potassium and potassium zirconium carbonate An organic-inorganic composite suitable for this application can also be obtained by using a chemical compound.

The manufacturing apparatus of the organic-inorganic composite in the present invention is not particularly limited as long as it is a manufacturing apparatus that can satisfactorily contact and react the aqueous solution (B) and the organic solution (A). It is also possible with the method. Specific equipment for the continuous type is "Fine Flow Mill FM-15" manufactured by Taihei Koki Co., Ltd., "Spiral Pin Mixer SPM-15" manufactured by the same company, or INDAG Machinenbau Gmb. "Dynamic mixer DLM / S215 type" manufactured by the company and the like can be mentioned. In the case of the batch type, since it is necessary to make good contact between the organic solution and the aqueous solution, a general-purpose stirring device having a propeller blade, a Max blend blade, a Faudler blade, or the like can be used.

  When an aliphatic diamine is used as the component in the aqueous solution (B) and an aliphatic dicarboxylic acid halide is used as the component in the organic solution (A), a strong gel may be generated during the polymerization operation. is there. In that case, it is preferable to use a mixer having a high shearing force for crushing the gel and advancing the reaction. Examples thereof include a blender manufactured by OSTERIZER.

  As for the temperature at which the organic solution (A) and the aqueous solution (B) are subjected to a polycondensation reaction, the reaction proceeds sufficiently in a temperature range of, for example, −10 to 50 ° C. near room temperature. Neither pressurization nor decompression is required. The polymerization reaction is usually completed in 10 minutes or less although it depends on the type of monomer used and the reactor.

  An electrochemical display medium can be obtained by holding the electrolytic solution in the organic-inorganic composite thus obtained. As a method for retaining the electrolytic solution, an organic-inorganic composite is introduced into a pre-prepared electrolytic solution and sufficiently dispersed and then filtered, or the electrolytic solution is circulated through the composite layer to replace the electrolytic solution. Examples include, but are not limited to, methods.

The organic-inorganic composite used in the present invention has extremely high electrolytic solution retention characteristics due to the presumed mechanism described above. Therefore, it is easy to filter the composite dispersion obtained by dispersing the composite in the electrolytic solution. A wet cake sheet holding an electrolyte solution of 4 to 25 times mass can be obtained only by performing the operation. Further, since the composite can be obtained in the form of a fiber or powder, the dispersion in the electrolytic solution can be easily performed using a general-purpose batch type stirring layer.

  When the organic-inorganic composite has a fiber shape, for example, a dispersion obtained by dispersing the composite in an electrolytic solution is filtered by a publicly known method to form a wet cake sheet without using any binder. It is possible. For example, a method of passing the dispersion liquid through a filter medium such as stainless steel or nylon mesh, a method of spraying the dispersion liquid on the substrate by spraying, and the like can be mentioned. By this method, an electrochemical display medium comprising a large-area wet cake sheet can be easily produced. Moreover, a well-known and usual binder can be used in the range which does not impair the electrolyte solution retainability, whiteness, and electronic insulation which are required.

On the other hand, when a composite having a powder shape is used, it is processed into a sheet shape by filtration in the same manner as a fiber-shaped composite by reducing the opening of the filter medium or mixing a binder having a fiber shape. I can do it. In addition, a binder that swells or gels with a polar solvent such as polyvinyl alcohol, cellulose derivative, polyacrylic acid, etc. in the composite, within a range that does not impair the required electrolyte solution retention, whiteness, and electronic insulation. After the addition, an electrochemical display medium having a wet cake sheet shape can be obtained by filtration or coating.

If the organic-inorganic composite is dried to a high solid content in the step of holding the electrolytic solution, the composite may be solidified solidly due to hydrogen bonds derived from the polar group of the organic component. Once the composite is solidified, it becomes difficult to re-disperse in the electrolyte, and the amount of electrolyte retained is greatly reduced. In addition, non-dispersed particles remain and the electrochemical display medium has uniform ionic conductivity and appearance. You will not be able to get. Therefore, it is preferable to perform the electrolyte solution holding operation in a wet cake state without drying the composite obtained by the polycondensation reaction. Preferably, a wet cake having a solid content of 35% by mass or less, more preferably 20% by mass or less is used. By taking the impregnation step of holding the electrolytic solution in the composite having such a solid content rate, an electrochemical display medium that holds the electrolytic solution at a high holding rate and has uniform ionic conductivity and appearance is obtained. Can do.

When the wet cake sheet obtained by the above method was prepared from an organic-inorganic composite containing an aliphatic compound as a monomer and containing 20% by mass or more of silica, aluminum oxide or zirconium oxide as an inorganic material, the wet cake sheet was calculated from the optical density. It has a pure white color with a reflectance exceeding 90%.

Moreover, since the wet cake sheet obtained by the above method holds 4 to 25 times mass and a large amount of electrolyte, it has an ionic conductivity close to that of the liquid in which the supporting electrolyte is dissolved. Keeps insulation.

The electrolytic solution used in the present invention is composed of a supporting electrolyte and a solvent for dissolving the supporting electrolyte. The solvent used in the present invention may be either aqueous or non-aqueous. In addition to water, propylene carbonate, dimethyl carbonate, 2-ethoxyethanol, 2-methoxymethanol, isopropyl alcohol, N-methylpyrrolidone, dimethylacetamide, dimethylformamide And polar solvents such as acetonitrile, butyronitrile, glutaronitrile, dimethoxyethane, γ-butyrolactone, ethylene glycol, and propylene glycol. In the case of an aqueous system, in order to satisfy the operation under a low temperature condition by preventing solidification at 0 ° C. or lower, among the above solvents, a solvent compatible with water can be used by being dissolved.

While various materials can be selected as the inorganic component of the organic-inorganic composite used in the present invention, the organic component is limited to polyamide, polyurethane, and polyurea. Since the refractive index of these organic polymers is around 1.5, when using an electrolytic solution having a high refractive index difference from the organic polymer constituting the composite, the decrease in whiteness of the composite due to immersion of the electrolytic solution is minimized. It is possible to obtain a display medium that is suppressed to the limit and maintains higher whiteness. When the organic polymer is polyamide 6.6, the refractive index of the polymer is 1.53. Therefore, a solvent having a refractive index of 1.40 or less, more preferably a solvent of 1.38 or less is used. Examples of such a solvent include water, acetonitrile, methanol, ethanol, acetonitrile, 2-ethoxyethanol, 2-methoxymethanol, isopropyl alcohol, and the like, and mixtures thereof.

  The supporting electrolyte constituting the electrolyte includes lithium salts such as lithium chloride, lithium bromide, lithium iodide, lithium perchlorate, lithium nitrate, lithium sulfate, lithium borofluoride, sodium chloride, sodium bromide, sodium iodide Examples thereof include alkali metal halides such as potassium chloride, potassium bromide, potassium iodide, tetrabutylammonium bromide, tetrabutylammonium chloride, tetraethylammonium borofluoride, ammonium salts such as borofluoride and trabutylammonium, and the like. .

  The electrode used in the present invention must be transparent if it is located on the viewing side. These include ATO (antimony tin oxide), TO (tin oxide), ZO (zinc oxide), IZO (indium zinc oxide), FTO in addition to ITO (indium tin oxide), which is currently most widely used. (Fluorine tin oxide) etc. can be illustrated. On the other hand, the electrode facing the transparent electrode does not necessarily need to be transparent. Therefore, in addition to the above metal oxide, an electrochemically stable metal such as platinum, gold, cobalt, palladium, or a carbon material should be used. You can also.

  The base material used in the present invention is not particularly limited as long as the material used on the viewing surface side has a smooth surface, high light transmittance, and the electrode can be installed. Specific examples include plastic sheets such as polyethylene terephthalate, polyester, and polycarbonate, and glass plates. In the case of the base material used on the opposite side of the viewing surface, the light transmittance need not be high.

There are two methods for introducing the decolored portion in the electrochemical display device of the present invention. As a first method, a color former that changes color by electrochemical oxidation-reduction is dissolved in an electrolytic solution in advance, and this is contained in the electrochemical display medium of the present invention. This is a method using a material that is colored by being precipitated and decolored by being dissolved.

The second method is a method in which a material layer that develops and decolors by changing the electrochemical oxidation level and reduction level is formed on the viewing-side electrode of the electrochemical display element of the present invention. is there

Among the above, in the first method, an organic compound and a metal compound that can coexist in a dissolved state in the electrolyte can be used. Examples of the organic compound used as the color former include organic quinones such as benzoquinone, naphthaquinone, anthraquinone, diphenoquinone, diphenylquinone, dibenzoanthraquinone, violanthrone, isoviolanthrone, and pyranthrone. These organic quinones are reduced by applying a driving voltage to the electrodes to produce a colored state peculiar to each compound. Examples of the metal compound used as the color former include halides such as silver, bismuth, copper, iron, chromium and nickel, sulfides, nitrates, perhalogenates and the like. By dissolving these compounds in the electrolytic solution, each metal is ionized, so that the electrolytic solution can be used as a color former. For example, when an electrolytic solution in which a silver compound is dissolved is used, when a driving voltage is applied to the electrode, a reduction reaction of Ag ⁺ + e ⁻ → Ag occurs on the cathode side, and the Ag deposit causes the black color on the electrode. To change. Among the above metals, bismuth and silver are particularly preferably used because they are almost transparent in a state dissolved in an electrolyte solution, and the precipitate has a deep color and a good decoloring reversible reaction. FIG. 1 shows the structure of a display element of a display device in which these color formers are coexisted in an electrolyte solution.

When the upper side of FIG. 1 is viewed, 1 is an organic-inorganic composite wet cake holding an electrolytic solution containing a color former and a supporting electrolyte, 2 is a transparent substrate such as glass or plastic, and 3 is transparent such as ITO. Electrode, 4 is a counter electrode, 5 is a sealant, and 6 is a counter substrate.

In the second method, a material layer that changes color by electrochemical oxidation or reduction is formed on one transparent electrode of two substrates having electrodes facing each other with the electrodes facing inside. Display is performed by the formed display element. In this method, an organic compound and a metal compound can be used as a material layer in contact with the electrode. Examples of the organic compound constituting the material layer include high molecular compounds such as polypyrrole, polyaniline, polyazulene, polythiophene, polyindole, and polycarbazole. In particular, polypyrrole has a dark precipitate color and is decolorized. It is preferably used because of its good reversible reaction. Examples of the inorganic compound constituting the material layer include WO3, MoO3, V2O5, Nb2O5, TiO2, NiO, Cr2O3, MnO2, CoO, and IrO2. In this method, it is necessary that a material layer causing such decoloring is formed on one transparent electrode of the substrate. When an organic compound is used as the material layer, the layer can be formed on the transparent electrode by electrolytic polymerization or chemical polymerization of the raw material monomer of the polymer compound. When a metal compound is used, it can be formed by a known method such as a vacuum deposition method, an electron beam vacuum deposition method, or a sputtering method. The structure of the display element of these display devices is shown in FIG.

Similar to FIG. 2, the various materials exemplified in the first method may be coated on the transparent electrode with a colorant-containing liquid or a gel material mixed with various binder resins together with the supporting electrolyte and the solvent. A display device can be manufactured. In this case, the colored layer can be provided by a coating method, a spin coating method, or the like.

2 is a transparent substrate such as glass or plastic, 3 is a transparent electrode such as ITO, 4 is a counter electrode, 5 is a sealant, 6 is a counter substrate, and 7 is a material. Layer 8 is an organic-inorganic composite wet cake holding an electrolytic solution containing a supporting electrolyte.

  A display device can be obtained by providing the display element shown in FIGS. 1 and 2 with a power supply portion, a circuit portion, a seal layer, a housing, and the like as necessary.

  Hereinafter, the present invention will be described more specifically with reference to examples. Unless otherwise specified, “part” means “part by mass”.

(Production Example 1: Synthesis of silica / polyamide organic-inorganic composite)
1.58 parts of 1,6-diaminohexane and 9.18 parts of water glass No. 3 were added to 81.1 parts of ion-exchanged water and stirred at 25 ° C. for 15 minutes to obtain a homogeneous transparent aqueous solution (B). This aqueous solution was charged into a blender bottle manufactured by Osterizer at room temperature, and an organic solution (A) in which 2.49 parts of adipoyl chloride was dissolved in 44.4 parts of toluene was stirred for 20 seconds while stirring at 10,000 rpm. It was dripped over. The generated gel was crushed with a spatula and further stirred at 10,000 rpm for 40 seconds. The liquid in which the pulp-like product obtained by this operation was dispersed was filtered under reduced pressure on a filter paper having a mesh size of 4 μm using a Nutsche having a diameter of 90 mm. The product on Nutsche was dispersed in 100 parts of methanol, stirred for 30 minutes with a stirrer, and filtered under reduced pressure for washing treatment. Subsequently, the same washing operation was performed using 100 parts of distilled water and filtration under reduced pressure to obtain a pure white silica / polyamide organic-inorganic composite wet cake (wet cake (1)).

(Production Example 2: Synthesis of aluminum oxide / polyamide organic-inorganic composite)
As an aqueous solution (B), 1.58 parts of 1,6-diaminohexane and 2.26 parts of sodium aluminate (Na2O / Al2O3 molar ratio = 1.3) are placed in 81.1 parts of ion-exchanged water and stirred at room temperature for 15 minutes. Then, a pure white aluminum oxide / polyamide organic-inorganic composite wet cake (wet cake (2)) was obtained in the same manner as described in Production Example 1 except that a homogeneous transparent aqueous solution (B) was obtained.

(Production Example 3: Zirconium oxide / polyamide composite)
As an aqueous solution (B), 1.58 parts of 1,6-diaminohexane and 3.79 parts of potassium zirconium carbonate (K2 [Zr (OH) 2 (CO3) 2]) were added to 38.5 parts of ion-exchanged water and stirred. A pure white zirconium oxide / polyamide organic-inorganic composite wet cake (wet cake (3)) was obtained in the same manner as described in Production Example 1 except that the obtained homogeneous solution was used.

(Production Example 4: Synthesis of polyamide containing no inorganic material)
An inorganic material was prepared by the same formulation and operation as the synthesis of the silica / polyamide organic-inorganic composite of Production Example 1 except that 1.18 parts of sodium hydroxide was added to the aqueous solution (B) instead of not containing water glass No. 3. Polyamide was synthesized without any inclusion. By this operation, a translucent polyamide wet cake (wet cake (4)) was obtained.

(Production Example 5: Production of nonwoven fabric of each material)
On a filter paper having a mesh size of 4 μm using a Nutsche having a diameter of 55 mm, 200 g of a dispersion obtained by dispersing the wet cakes (1) to (4) obtained in Production Examples 1 to 4 in distilled water at a concentration of 0.2 g / dL. And filtered under reduced pressure. The obtained cake was hot-pressed at 170 ° C. and 5 MPa / cm ² for 2 minutes to prepare a nonwoven fabric. The obtained non-woven fabric was rich in flexibility, and even if it contained an inorganic material or was bent, no particles dropped off.

(Production Example 6: Production of electrolyte solution having color former and supporting electrolyte)
As a solvent, a mixed solvent of 4.0 parts of acetonitrile and 4.0 parts of water was prepared. By dissolving 0.2 parts of silver perchlorate as a color former and 2.0 parts of lithium perchlorate as a supporting electrolyte in the solvent to obtain a homogeneous transparent liquid, an electrolyte solution having a color former was prepared.

<Evaluation of material properties of organic-inorganic composite and polyamide>
(1) Measuring method of inorganic component content rate (ash content) The measuring method of the content rate of the inorganic component contained in each material is as follows.
After each material is completely dried, it is precisely weighed (composite mass), calcined in air at 600 ° C. for 3 hours to completely burn off the polymer component, and the mass after firing is measured to measure the mass of ash (= inorganic component mass). It was. The inorganic content was calculated according to the following formula.
Inorganic component content (mass%) = (ash content / composite mass) × 100

(2) Verification of metal compound species in organic-inorganic composites (FP method)
A non-woven fabric was cut into 3 cm square, and this was set in a measurement holder having an opening of 20 mm in diameter to obtain a measurement sample. The sample was subjected to total elemental analysis using a fluorescent X-ray analyzer “ZSX100e” manufactured by RIKEN ELECTRIC CO., LTD. Using the obtained results of total elemental analysis, the sample data of the sample for measurement (the data given is sample shape; film, compound type; oxide, correction component: cellulose, mass value per area of the measured sample) Presence of elements in the complex by the FP method (Fundamental Parameter method; a method in which sample uniformity and surface smoothness are assumed and correction is performed using constants in the device to determine the components) The percentage was calculated. Moreover, the amount of inorganic components calculated from the FP method showed good agreement with the value calculated from the ash content measuring method of (1). From this value, the target inorganic component (silica when water glass is used as raw material, aluminum oxide when sodium aluminate is used, zirconium oxide when potassium zirconium carbonate is used) is contained in the organic-inorganic composite. It was verified that a large amount (40% by mass or more) was present.

  In this measurement, alkali metal (sodium) was detected only in an amount of 0.03% by mass or less in any of the examples and comparative examples. Polymer polycondensation in the present invention, alkali metal removal from inorganic raw materials, and inorganic material It was revealed that the solidification reaction was carried out according to the predicted reaction mechanism.

(3) Measurement of particle size of inorganic component in organic-inorganic composite and observation of dispersion state The organic-inorganic composite was hot-pressed for 2 hours under the conditions of 170 ° C. and 20 MPa / cm ² , and the organic-inorganic composite having a thickness of about 1 mm. A flake consisting of the composite was obtained. This was made into an ultrathin section having a thickness of 75 nm using a microtome. The obtained section was observed with a transmission electron microscope “JEM-200CX” manufactured by JEOL Ltd. at a magnification of 100,000. It was observed that the inorganic component was finely dispersed in a bright organic polymer as a dark image. The particle diameter of 100 inorganic particles was measured, and the average value was defined as the inorganic component average particle diameter. In this observation, it was observed that in the silica / polyamide composite, the inorganic component (silica) of about 10 nm was network-like, that is, a three-dimensional network was formed and finely dispersed in the polyamide. In the aluminum oxide / polyamide organic-inorganic composite, it was observed that about 10 nm of aluminum oxide was layered, that is, formed in a two-dimensional network and finely dispersed in the polyamide. On the other hand, in the zirconium oxide / polyamide organic-inorganic composite, it was observed that each of the zirconium oxide particles in the vicinity of 850 nm was dispersed independently.

(4) Production of Wet Cake Sheet Display Medium Retaining Electrolyte Solution After measuring the weight of each of the obtained wet cakes (wet weight), it was dried at 150 ° C. for 2 hours, and the weight was measured (dry weight). From these numerical values, the solid content ratio of the wet cake was calculated by the following equation.
Solid fraction (mass%) = (dry weight / wet weight) × 100
Each wet cake calculated so that the solid content of the sample was 0.3 g from this solid content ratio was stirred and dispersed in 10 g of an electrolyte prepared in advance at room temperature for 10 minutes, and then on a 4 μm filter paper. A wet cake sheet type display medium was produced by filtering under reduced pressure at 0.02 MPa for 5 minutes.

(5) Measurement of electrolyte holding amount with respect to weight of complex Perform the same operation as (4), measure the weight of wet cake after filtration under reduced pressure, and how many times the complex holds the electrolyte. Was calculated.
Electrolyte retention amount (times) = (weight of wet cake−0.3) /0.3
Even when the wet cake sheet in this state was sandwiched between plate glasses and compressed, no leakage of the electrolyte solution was observed.

(6) Measurement and calculation of reflectivity of wet cake sheet in air Place a wet cake sheet of about 400 μm thickness prepared by the method of (4) on a standard black plate, and set the optical density value (OD value). Measurement was performed using a reflection densitometer Macbeth RD-918, and the reflectance of the wet cake sheet was calculated from the measured value based on the following formula.
Reflectance (%) = 10− ^{(OD value)} × 100

  For the polyamides not containing the organic-inorganic composites and inorganic materials obtained in Production Examples 1 to 4, the following items were measured or tested, and the results obtained are shown in Table 1.

<Display characteristics evaluation of display device>
(Production of display element and device for example)
(Example 1) Using a wet cake sheet of silica / polyamide composite as a display medium 2.14 g of wet cake (1) having a solid content of 14% by mass of the silica / polyamide organic-inorganic composite synthesized in Production Example 1 The mixture was stirred and dispersed in 10 g of an electrolytic solution prepared by the method described in Production Example 6 at room temperature for 10 minutes. By this operation, a uniform composite dispersion was obtained. The dispersion was filtered under reduced pressure at 0.02 MPa for 5 minutes on 4 μm filter paper. The obtained wet cake sheet was again dispersed in the electrolytic solution by the same treatment as the first time, and then filtered under reduced pressure to prepare a wet cake sheet type display medium. A display element was fabricated by sandwiching both sides of the display medium with ITO electrodes having a glass substrate (surface resistance: 10Ω / □) with a thickness of 500 μm so that the electrode surface is inside, and sealing the periphery with an epoxy resin. A display device was produced by connecting the ITO electrode of the display element to a power source with a function generator.
Example 2 Using a wet cake sheet of aluminum oxide / polyamide composite as a display medium A wet cake (2) having a solid content of 17% by mass of the aluminum oxide / polyamide organic-inorganic composite synthesized in Production Example 2 was A display medium was produced in the same manner as in Example 1 except that 76 g was used. In addition, a display element and a display device were manufactured by the same method.
Example 3 Using a wet cake sheet of zirconium oxide / polyamide composite as a display medium 1. A wet cake (3) having a solid content of 16% by mass of the zirconium oxide / polyamide organic-inorganic composite synthesized in Production Example 3 was obtained. A display medium was produced in the same manner as in Example 1 except that 88 g was used. In addition, a display element and a display device were manufactured by the same method.

(Production of display element and device for comparative example)
(Comparative Example 1)
The display medium was prepared in the same manner as in Example 1 except that 1.20 g of a wet cake (4) having a solid content of 25% by mass of polyamide having no inorganic component was used instead of the organic-inorganic composite as the display medium material. Was made. In addition, a display element and a display device were manufactured by the same method.
(Comparative Example 2)
A display device similar to that of the example was manufactured except that, as a material for the display element, high-quality paper superposed so as to have a thickness of 500 μm was used instead of the organic-inorganic composite.
(Comparative Example 3)
The silica / polyamide composite used in Example 1 was sealed below the counter substrate 6 in FIG. 1 (on the opposite side to the viewing surface) without putting a material such as an organic-inorganic composite between the electrodes. A display device was produced in the same manner as in the example except that a wet cake sheet was installed.
(Comparative Example 4)
According to Example 4 of Patent Document 3, an electrodeposition type display device was produced using a mixture of polyvinylidene fluoride, LiBF ₄ , and AgClO ₄ as a polymer solid electrolyte.

(Measurement and calculation of white reflectance of display device)
The display devices prepared as the above examples and comparative examples were placed on a standard black plate, and the optical density value (OD value) in a state where no voltage was applied was measured with a reflection densitometer Macbeth RD-918. The white reflectance was calculated by the same method as the reflectance of the wet cake sheet.

(Observation of texture)
From the viewpoint of how close the texture of the display part in each of the Examples and Comparative Examples in the state where the white reflectance of the display device was measured was judged visually in three stages. ○ means close to high-quality paper, Δ means slightly close to high-quality paper, and x means clearly different from high-quality paper.

(Contrast measurement and calculation)
An electric field of −1.5 V / mm was continuously applied to the display device for 10 seconds. Thereby, the visual surface side of the display device was changed to black by the deposition of silver. In this state, application of the electric field was stopped, and the reflectance (black reflectance) of the obtained black display device was measured and calculated in the same manner as the white reflectance described above. The obtained black reflectance and white reflectance were expressed as a ratio, and this ratio was defined as contrast.

Table 2 summarizes the evaluation results of the display characteristics of the obtained display device.

  As shown in Table 2, it can be seen that the display device manufactured using the display medium according to the present invention has high white reflectance, close to the texture of paper, and high contrast. In addition, since the electrolytic solution held in the organic-inorganic composite in an amount of 5 times or more of its own weight is used as the electrolyte, the decolorization rate (as compared with Comparative Example 4 using the solid polymer electrolyte as the display medium) Responsiveness) and excellent blackness during coloring. In Comparative Examples 1 and 2, since the member inside the element does not have sufficient electrolytic solution holding power, uniform decolorization over the entire display surface of the device is smoothly caused due to insufficient ion movement in the electrolytic solution. It did not occur and the contrast ratio was lower than the others. In Comparative Example 3, the high reflectance inherent to the composite wet cake sheet is that the incident light passes back and forth through the two glass substrates on the front surface of the composite, the two ITO electrodes, and the electrolyte. It attenuated greatly at. Moreover, in Comparative Examples 1-3, since electrolyte solution was not fully hold | maintained in the element, when damage | damage of an element generate | occur | produced, it was estimated that electrolyte solution leaks.

  Moreover, the outstanding characteristic as a display medium of the organic-inorganic composite shown by Examples 1-3 of Table 2 is that the inorganic material of submicron-nano size is disperse | distributing in the organic material (refer Table 1). ) Greatly contributed to the whiteness and the electrolyte retention amount, which are important for display characteristics, and it was shown that this characteristic cannot be achieved by polyamide alone.

  The present invention provides a reflective electrochemical display medium that has very close visibility and texture similar to paper, a display element using the same, and a display device.

FIG. 3 is a schematic view of a display element using a wet cake holding an electrolytic solution in which a color former coexists in a dissolved state in the present invention. FIG. 3 is a schematic view of a display element in which a material layer that is discolored by electrochemical oxidation or reduction is formed on a transparent electrode and a wet cake holding an electrolytic solution is disposed below the transparent electrode in the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Organic inorganic composite wet cake sheet | seat holding the electrolyte solution containing color former and supporting electrolyte 2 Transparent base material 3 Transparent electrode 4 Opposite electrode 5 Sealing agent 6 Opposite base material 7 Color developing material layer 8 Electrolysis containing supporting electrolyte Organic-inorganic composite wet cake sheet holding liquid

Claims (9)

An organic solution (A) in which one kind of compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound and a phosgene compound is dissolved in an organic solvent;
At least one metal compound selected from the group consisting of metal oxides, metal hydroxides, and metal carbonates, having an alkali silicate and / or two or more metal elements and one of the metal elements is an alkali metal ( 1) and a basic aqueous solution (B) containing a diamine are mixed and stirred, and a complex of an organic polymer and an inorganic compound obtained by polycondensation reaction. An electrochemical display medium characterized by being held. The electrochemical display medium according to claim 1, wherein the composite holds an electrolyte having a mass of 4 to 25 times its own weight. The electrochemical display medium according to claim 1, wherein the composite has a pulp shape with a fiber diameter of 20 μm or less and an aspect ratio of 10 or more. The electricity according to any one of claims 1 to 3, wherein the inorganic compound constituting the complex is a metal compound and / or silica selected from the group consisting of aluminum oxide, zirconium oxide, zinc oxide, and tellurium oxide. Chemical display medium. The electrochemical display medium according to claim 1, wherein the electrolytic solution has a color former that changes color by electrochemical oxidation and reduction. The electrochemical type display element which has the electrochemical type display medium of Claim 5 between the board | substrates which made two board | substrates which have an electrode mutually opposing by making this electrode inside. An electrochemical display medium according to any one of claims 1 to 4 is provided between two substrates having electrodes facing each other with the electrodes facing inside, on one electrode of the substrate An electrochemical display element having a material layer that changes color due to electrochemical oxidation and reduction. An electrochemical display device comprising the electrochemical display element according to claim 6. An organic solution (A) in which one kind of compound selected from the group consisting of a dicarboxylic acid halide, a dichloroformate compound and a phosgene compound is dissolved in an organic solvent;
At least one metal compound selected from the group consisting of metal oxides, metal hydroxides, and metal carbonates, having an alkali silicate and / or two or more metal elements and one of the metal elements is an alkali metal ( 1) and a basic aqueous solution (B) containing a diamine are mixed and stirred, and a composite synthesis step for obtaining a composite of an organic polymer and an inorganic compound obtained by polycondensation reaction;
A method for producing an electrochemical display medium, comprising: an impregnation step of impregnating an electrolytic solution in a state where the solid content of the composite is 35% by mass or less and retaining the electrolytic solution in the composite.

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